Fuel vapor supply system for vehicle heaters



Oct. 28, 1947. H. D. PINKERTOYN ET AL. 2,429,842

' FUEL VAPOR SUPPLY SYSTEM. FOR vmucma nmwsns Filed July 5, 1943 INVENTOR$ Harry 0. Pmkerfqn, e C/arence .5. P/remc/e,

"Q"? 1 ATTORNEYS.

Patented Oct. 28,1947

FUEL VAPOR SUPPLY SYSTEM FOR VEHICLE HEATERS Barry D. Pinkerton and Clarence S. Phenicla Kansas City, Karla, asslgnon atone-third to Ellsworth H. Munford, Kansas City, Mo.

f Application July 5, 1943, Serial No. 493,536

tallic compounds such as tetraethyl lead for the prevention of ignition knocks. These fuels do not operate satisfactorily in liquid hydrocarbon burning equipment because the metallic compounds decompose at vaporizing temperatures of .the fuel and the resulting deposits clog up the vaporizing passages and orifices of the burners.

Therefore it is a principal object of the present invention to provide for operation of such burners by the vapors evolved within the tank containing the hydrocarbon fuel supply for the vehicle. In this way, th more volatile fractions of the fuel supply, in vapor form, are free from the objectionable compounds and will burn satisfactorily in gas burners. Other objects of the invention are to provide for storage of the vapors under pressure so as to provide an adequate instantly available reserve supply; to provide for release of the stored vapors at the low pressure required for satisfactory burning in a low pressure gas burner; to provide for automatic operation of the vapor pump and compressor responsive to pressure of the stored vapor; and to provide a fuel supply and burner which is safe in operation.

In accomplishing these and other objects of the invention we have provided improved structure, the preferred form of which is illustrated in the accompanying drawing wherein:

Fig. l is a side elevational view of a motor vehicle equipped with a heater and a gaseous fuel supply apparatus for the heater.

Fig. 2 is a perspective view of the heater as viewed from the fan side thereof and showing connection with the gaseous fuel supply apparatus, the electrical control circuits being shown in diagram.

Fig. -3 is a vertical section through the heater particularly illustrating the construction thereof.

Referring more in detail to the drawings:

l designates an internal combustion engine powered vehicle, for example a motor vehicle having a passenger compartment 2 which for comfort must be heated in cold weather. Various types of heaters have been designed for this purpose but the most satisfactory is an air circulating Claims. (01. 158-28) unit heated by a burner using a part of the fuelsupply-to the engine. However, as above mentioned, motor fuels contain anti-knock compounds such as tetraethyl lead which decompose when the liquid hydrocarbon is vaporized by heat and the decomposition results in deposits which soon clog the vaporizer and orifices controlling fuel supply to the burner. In overcoming this dimculty, we provide a heater 3 including a framelike casing 4 open at the front and rear' sides and having a burner chamber 5 at the bottom thereof connected by a plurality of tubes 6 with a vent chamber I. The tubes 6 are spaced apart to form air passageways 8 therebetween for flow of air to be heated, the flow of air being maintained in circulation within the passenger compartment of the vehicle by a fan 9 actuated by an electric motor I0 supplied with current from the storage battery II in the vehicle. The motor III is supported with the fan in position to discharge the air through the passageways 8 by means of a spider-like frame l2 carried by the heater casing 4. The heater casing may be located in any convenient position within the passenger compartment but is preferably mounted on the dash I3 whereby a vent pipe l4 connected with the vent chamber 1 is led through thedash to discharge fumes resulting from burning of fuel within the burner chamber 5. The pipe l4 preferably extends downwardly after passing through the dash and terminates below the body of the vehicle in an outlet 15 curved toward the rear so that rush of air over the outlet assists in withdrawal of gases from the vent chamber. Secondary air is supplied to the burner chamber through a pipe I6 having an inlet preferably extending into the motor compartment of the vehicle so that the secondary air is taken exteriorly of the passenger compartment.

Mounted within the burner chamber is a preferably low pressure gas burner I! having a plurality of gas outlets I8 located under the lower ends of the tubes 6 so that the resulting flames play upwardly within the tubes to heat the walls thereof, the heat being absorbed by the air circulated around the tubes. The burner l! includes a duct portion I9 connected with a fuel supply pipe 20 having a nozzle 2| for discharging a gaseous fuel into the burner. The supply. pipe 20 may be provided with suitable fire stops 22 as in conventional gas burning equipment.

In carrying out the present invention, we provide for a supply of gaseous fuel taken from the vapors accumulating in the vapor space 23 within the fuel tank 24 of the vehicle. A pipe 25, being connected with the top of the tank, leads forwardly of the vehicle and connects with a vapor pump and compressor unit 26. The unit 28 includes a lower cup-like housing 21 enclosing an electromagnet 28 and an armature 29 reciprocable thereby responsive to flow of an intermittent current through a magnet winding, the current being preferably supplied from the automobile battery I through a circuit including a conductor 30 having connection with the winding of the magnet throughcircuit breaking contacts 3| and 32 that are adapted to be opened and closed responsive to movement of the armature by means of an arm 33 mounted on the armae ture and projecting to engage the movable contact 3| of the circuit breaker as shown in Fig. 2. Circuit is completed to the battery through a ground connection 34. Connected with the armature 29 is a bellows type pump 35 carried by a e 35 closing the D of the cup-like housing 21, the head having a portion 31 drilled to accommodate a check valve 38 for closing an inlet port 39 having connection with the pipe 25, the

valve being retained in seated position by a with the part 21 by fastening devices such as screws 45 extending through suitable flanges in cup-like members and through registerin openings in the head 36. The vapor storage chamber 44 is connected by a pipe 41 with a pressure regulating valve 48 set to deliver the stored vapor to the burner at a relatively low pressure through a pipe 49 that is connected with the pipe 20 by a magnetic valve 50. The magnet of the valve 50 is arranged to open the valve upon closing of a switch in the conductor 30 of the battery circuit. Current is supplied to the magnet switch through a conductor 52 and ground connection 53 as shown in Fig. 2. The motor Ill is preferably' connected with the circuit 30 on the open side of the switch 5| so that the motor H1 is energized whenever the switch is closed to effect opening of valve 50 and actuation of the vapor 4 44 on the contraction stroke of the bellows. Upon removal of vapor from the vapor space of the tank an air supply is drawn through the breather orifice (not shown but usually located in the filler cap 59 of the tank) which air mixes with the vapor accumulatin withinthe space 23 and forms an initially combustible mixture, This mixture is stored within the relatively small chamber 44 up to the pressure capacity of the pump, for example four or five pounds, at which pressure the contacts 3|, 32 are held closed and the pump stops. The regulator 48 is designed to release the mixture at a lower pressure suitable for satisfactory burning operation, for example, a pressure of four or five ounces.

Simultaneously with closing of the switch 5|, the motor [0 is energized to actuate the fan for circulating the air in the passenger compartment of the vehicle through the heater unit. Since the burner chamber is cold the thermostat is closing circuit to the igniter for lighting the burner. As the burner warms the heater casing, the thermostat 56 opens the igniter circuit until the fiame of the burner becomes extinguished or the switch 5| opened to suspend operation of the burner.

Attention is directed to the fact that the air 7 being drawn across the surface of the liquid fuel pump. In order to automatically effect lightin of the burner, the burner chamber is provided with an igniter 54 located at one end of the burner and which is supplied with an igniting current through a conductor 55 connected with a thermostat 56 mounted on the side wall of the burner chamber 5 and which connects with the conductor 51 supplying the motor II), the motor circuit being completed through a ground connection 58.

With this arrangement the thermostat switch 56 when cold closes circuit to the igniter to effect ignition of the vapors discharged through the outlets of the burner. As soon as the heater has warmed up, the thermostat switch will open the igniter circuit; therefore, the igniter is in operation only when the switch 5| is closed and the burner chamber is cold.

In operating a heater constructed and installed as described, the switch 5| is closed to energize the electrical magnet of the pump compressor unit 26 to effect drawing of vapor from the vapor space of the tank 23 through the pipe 25 to the bellows of the pump on the expansion stroke thereof to be expelled into the storage chamber in the tank facilitates vaporization and assures a constant supply of vapor for use in the burner. It is to be noted however that vapors are being drawn from the tank only during intervals of pump operation, and any vaporizing effect through withdrawal of vapors is suspended when the pump ceases to operate.

From the foregoing it is obvious that we have .provided a burner type heater with fuel evolved from the vaporization of the liquid hydrocarbon motor fuel within the tank 24 so that the gaseous fuel supplied to the burner is entirely free of the metallic compounds and other objectional matter ordinarily contained in motor fuels.

What we claim and desire to secure by Letters Patent is:

1. In a heating and fuel supply apparatus for a motor vehicle, a container for a body of volatile liquid'hydrocarbon providing a source of fuel,

supply for the motor of the vehicle and having a vapor space over the body of fuel when the fuel is placed in the container and into which vapors of the liquid hydrocarbon accumulate, a heater, a vapor fuel burner for the heater, duct means connecting the vapor space of the container with the burner, a pump having connection with the duct means for effecting withdrawal of vapor from said vapor space through the duct means and discharging the vapor under pressure to the burner. a vapor storage container interposed in the duct means between the pump and the burner for storing vapor under pressure in excess of that required to operate the burner, and an actuator for the pump.

2. In a heating and fuel supply apparatus for a motor vehicle, a container for a body of volatile liquid hydrocarbon providing a source of fuel supply for the motor of the vehicle and having a vapor space over the body of fuel when the fuel is placed in the container and into which vapors of the liquid hydrocarbon accumulate, a heater, a vapor fuel burner for the heater, duct means connecting the vapor space of the container with the burner, a pump having connection with the duct means for effecting withdrawal of vapor from the vapor space and dischargin the vapor through the duct means under pressure to the burner, a vapor storage container interposed in the duct means between the pump and the burner for storing vapor in excess of that required to operate the burner, an actuator for the pump. and means for controlling operation of the actuator to stop pumping responsive to a predetermined pressure in the vapor storage container.

3. In a heating and fuel supply apparatus for a motor vehicle, a container, for a body of volatile liquid hydrocarbon providing a source of fuel supply for the motor of the vehicle and having a vapor space over the body of fuel when the fuel is placed in the container and into which vapors volatilized from the liquid hydrocarbon accumulate, a heater, a vapor fuel burner for the heater, duct means connecting the vapor space of the container with the burner, a pump having connection with the duct means for efiecting withdrawal of vapor from the vapor space and discharging the vapor through the duct means under pressure to the burner, a vapor storage container interposed in the duct means between the pump and the burner for storing vapor under pressure in excess of that required to operate the burner, an actuator for the pump, means for controlling operation of the actuator to stop pumping responsive to a predetermined pressure in the vapor storage container, and a pressure reducing valve in the duct means be-- tween the vapor storage container and the burner for supplying vapor from the vapor storage container at a pressure required by the burner.

4. In a heater and fuel supply apparatus for amotor vehicle, a container for a body of volatile liquid hydrocarbon providing a source of fuel supply for the motor of the vehicle and having a vapor space above the body of volatile liquid hydrocarbon and into which vapors volatilized from the liquid hydrocarbon are adapted to accumulate when said fuel is placed in the container, a heater, a vapor fuel burner for the heater, duct means connecting the vapor space of the container with the burner, a pump having connection with the duct means for effecting withdrawal of vapor from the vapor space and discharging the vapor through the duct means under pressure to the burner, a vapor storage container interposed in connection with the duct means between the pump and the burner for storing vapor under pressure in excess of that required to operate the burner, an actuator for the pump, means for coning flow of vapor to the burner.

5. In a heater and fuel supply apparatus for a motor vehicle, a container for a body of volatile liquid hydrocarbon providing a source of fuel supply for the motor of the vehicle and. having a space above the body of volatile liquid hydrocarbon and into which vapors volatilized from the liquid hydrocarbon are adapted to accumulate when said fuel is placed in the container, a heater, a vapor fuel burner for the heater, duct means connecting the vapor space of the container with the burner and having storage for vapors under pressure in excess of that required to operate the burner, a pump having connection with the duct means for efl'ectng withdrawal of vapor from the vapor space and discharging the vapor through the duct means under pressure to the burner, an actuator for the pump, means for controlling the actuator to stop pumping responsive to a predetermined pressure maintenance in the duct means, and a pressure reducing valve in the duct means ahead of the burner for passing vapor at the pressure required by the burner.

HARRY D. PINKERTON. CLARENCE S. PHENICIE.

REFERENCES CITED The following references areof record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,191,178 'McCollum Feb. 20, 1940 1,757,840 Lea May 6, 1930 2,027,879 Piscionere Jan. 14, 1936 1,528,930 Plant et a1. Mar. 10, 1925 1,631,859 Goodridge June 7, 1927 1,513,511 Hromas Oct. 28, 1924 1,907,924 Wilson May 9, 1933 2,864,457 McCollum Dec. 5, 1944 

